Sun & Seed Nutrition Science Library · Series 11: Activated Nuts
“Activated nuts” have become a familiar term in the health-food market. The process usually involves soaking raw nuts in water, sometimes with added salt, before drying them again at a low temperature. The resulting product is marketed as easier to digest, more nutritious or better able to release its minerals during digestion.
The explanation most often given is that soaking reduces phytic acid, a naturally occurring compound that can bind minerals such as iron and zinc. Some proponents also suggest that soaking mimics the beginning of germination, activating enzymes and making the nutrients in nuts more available to the body.
These claims sound plausible. But when researchers have directly investigated the effects of activating nuts, the findings have been much less impressive than the marketing suggests.
What does “activation” actually mean?
Unlike sprouting, which involves a seed beginning to germinate, activating nuts generally means soaking them in water for a period of time and then drying them.
The precise method varies between producers. Nuts may be soaked for several hours, sometimes in salted water, and subsequently dehydrated. The process can soften the nuts and change their surface characteristics, flavour and texture.
However, soaking does not automatically mean that germination has occurred. Many commercially sold nuts are not viable seeds, and a typical soaking process does not necessarily trigger the coordinated metabolic changes associated with germination.
This distinction matters because evidence about sprouted grains or legumes cannot simply be applied to soaked almonds, walnuts or hazelnuts.
Phytate: the main nutritional claim
Phytate is the principal storage form of phosphorus in many seeds, nuts, grains and legumes. It can bind minerals and reduce their absorption under certain dietary conditions. Its effect depends on the food, the mineral involved, the wider meal and the overall diet.
The argument for activating nuts is that soaking reduces phytate, thereby improving mineral availability.
There is a problem with this argument: soaking a nut does not guarantee that much phytate will be removed. The extent of any change depends on the nut's enzyme activity, the conditions used and whether compounds can diffuse into the soaking water.
One of the most directly relevant studies was published in Food Chemistry in 2020. Kumari and colleagues examined the effects of different soaking conditions on almonds, hazelnuts, peanuts and walnuts.
The researchers found that phytate changes were relatively small, ranging from approximately a 12% reduction to a 10% increase, depending on the nut and soaking conditions. Mineral concentrations also frequently declined. The researchers concluded that their findings did not support claims that activating nuts improves mineral bioavailability.
This is an important result because it examines the nuts themselves rather than assuming that a process effective in one food will work equally well in another.
Even a measured reduction in phytate would not, on its own, prove that a person absorbs more iron, zinc or other minerals after eating the nut. That would require evidence of improved bioavailability, and ideally evidence from studies in people.
Does soaking make nuts easier to digest?
Another common claim is that activated nuts are easier on the digestive system.
A randomised crossover study published in the European Journal of Nutrition in 2018 examined whether soaking almonds improved gastrointestinal tolerance or consumer acceptance. The trial included 76 participants who consumed almonds prepared in different ways.
The researchers found no improvement in gastrointestinal tolerance from soaking. Flatulence was slightly higher after participants consumed soaked whole almonds, and the study did not find the expected reduction in phytate.
The results do not prove that nobody will find soaked nuts easier to eat. Individual responses can differ, and a softer texture may be more comfortable for some people. But they do not support a general claim that activation improves digestive tolerance.
There is also a practical distinction between a nut feeling softer and being more digestible in the nutritional sense. Softening changes texture. Improved digestibility would mean that the food's components are broken down or absorbed more effectively, which needs to be demonstrated separately.
What happens to the nutrients?
Soaking can cause changes in the composition of nuts, but the effects are not uniformly beneficial.
Water-soluble compounds may leach into the soaking water. Depending on the conditions, this can include some minerals and other soluble components. If the soaking water is discarded, any nutrients that have migrated into it are discarded as well.
The nut's water content also increases during soaking. If nutrient concentrations are compared on a fresh-weight basis rather than a dry-weight basis, this change can make the results misleading. A lower concentration per 100g of soaked nut may partly reflect additional water rather than a true loss of that proportion of the nutrient from the original nut.
Drying the nuts afterwards introduces further variables, including the temperature used, the time required and the potential for oxidation or other changes during processing.
The appropriate way to assess the nutritional effect is therefore to compare the original nuts with the finished activated product using consistent analytical methods and a clear basis for calculating nutrient retention.
There is currently no strong basis for assuming that activated nuts are generally more nutritious than untreated nuts.
Does activation improve flavour and texture?
This is where the process may have a more straightforward rationale.
Soaking hydrates nuts and changes their texture. After drying, the finished product may differ in crispness, bite and flavour from a conventional raw or roasted nut. Some consumers may prefer these characteristics, while others may prefer the familiar crunch of roasted nuts.
The outcome depends on the nut and the process. Drying conditions, residual moisture, roasting and seasoning can all influence the final product.
These are legitimate reasons to prefer a soaked-and-dried nut. They are sensory preferences, however, rather than proof of improved nutritional value.
What about food safety?
Soaking introduces moisture, and moisture can create conditions in which microorganisms grow if time, temperature and hygiene are not properly controlled.
Nuts are generally shelf-stable when sufficiently dry. Once hydrated, they need to be managed as a different product until the drying process has restored an appropriate level of stability.
Safe production therefore depends on controlled soaking, handling, drying and final moisture. Drying alone should not be assumed to eliminate every relevant pathogen.
Nuts also contain unsaturated fats that can oxidise, so soaking and drying can affect flavour stability as well.
Activated nuts versus sprouted seeds
The two processes are often grouped together in health-food marketing, but they should not be treated as equivalent.
Sprouting (covered in our companion article, Sprouted Seeds: What Does the Science Tell Us About Their Nutritional Value?) involves germination and the activation of biological processes that help a seed begin growing. These processes can alter phytate, stored nutrients and other compounds. The magnitude of the changes varies widely, and the resulting ingredient still requires nutritional and safety evaluation.
Activating nuts generally involves hydration followed by drying, without necessarily producing germination. Research directly examining activated nuts has not demonstrated the broad improvements in mineral bioavailability or digestive tolerance that are commonly claimed.
This does not mean that soaking is useless. It means that its value should be assessed according to what it actually does to the product.
Conclusion
Activated nuts are an example of a food-processing trend whose nutritional claims have moved further than the available evidence.
Direct research on almonds, hazelnuts, peanuts and walnuts found that soaking produced relatively small and inconsistent changes in phytate, while mineral concentrations often declined. A separate human trial found no improvement in gastrointestinal tolerance from soaking almonds.
The evidence does not establish that activated nuts are generally easier to digest or provide minerals more effectively than untreated nuts. Soaking may still be useful for texture, flavour or a particular product concept, but these benefits should be assessed on their own merits.
For consumers, ordinary nuts remain a valuable source of nutrients without requiring an activation step.
References and further reading
- Kumari S, Gray AR, Webster K, Bailey K, Reid M, Kelvin KAH, Tey SL, Chisholm A, Brown RC. Does ‘activating’ nuts affect nutrient bioavailability? Food Chemistry. 2020;319:126529. https://doi.org/10.1016/j.foodchem.2020.126529
- Taylor H, Webster K, Gray AR, Tey SL, Chisholm A, Bailey K, Kumari S, Brown RC. The effects of ‘activating’ almonds on consumer acceptance and gastrointestinal tolerance. European Journal of Nutrition. 2018;57(8):2771–2783. https://doi.org/10.1007/s00394-017-1543-7
Editorial note: This is a narrative research article, not a systematic review. It draws mainly on two studies from the same research group, so further independent research would strengthen the conclusions. This article is intended for general nutrition education, not individual medical advice.
